A save file containing the fortress known as Weatherwires.

Includes a bug preventing dwarves from breeding (there are only 93 left), and a large dome which can be flooded with magma. Inside the dome is a dwarven city carved from rock, which matches the layout of the procedurally generated cavern layer below. Why do the dwarves live in a dome that is periodically filled with molten rock? If you have to ask, you obviously haven't been playing this game for long enough.